Croft



Patented Dec. I3,f|8 98.

.1. a. J. E. THURNYCRUFT.

STEAM TRAP.

[Application led May 2, 1898.) .v

(No Model.)

PETERS co.. Pnomuwafwnmom', D. c.

UNITED STATES l' PATENT EFICE.

JOHN ISAAC THORNYCROFT AND JOI-IN EDVARD THORNYCROFT, OF LONDON, ENGLAND;

STEAM-TRAP;

SPECIFICATION forming part of Letters Patent N0. 615,764, dated December 13, 189'8. Application filed May 2, 1898. Serial No. 679,439. (No model.)

of the kind constructed with parts ofmaterial Y which at a given temperature have a greater coeftlcient of expansion than other parts and in which the opening and closing of valves are due to such differences.

Our object is in apparatus of this class to provide for the ready opening, in the manner indicated, of valves of larger area than has heretofore been usual, so that a large quantity of water, such as the priming-water col-l lected in the separator or separators of main steam-pipes, can be quickly discharged. For this purpose we construct apparatus with a comparatively large valve which we will call the main valve and with a supplementary or smaller valve which we will call the controlling-valve and which alone is or may be opened and closed by the action of parts of the apparatus due to diierences in expansion and contraction, the main valve being operated by fluid-pressure.

As will be obvious, our invention can be applied in connection with various forms of steam-traps of the kind above referred to.

Figure 1 of the accompanying illustrative drawings shows partly in side elevation and partly` in longitudinal vertical section one construction of expansion steam-trap according to this invention. Fig. 2 is a detail view showing a modiied construction.

1 is a valve-case formed with two passages 1n and 1b and an annular connecting-passage 1C, surrounding the upper end of the passage 1". This valve-case is arranged to constitute a junction-piece between the adjacent ends of two pipes 3 and 4, which are screwed into it, and the other ends of which are secured to a bracket or carrier 5 and are provided with connections G and 7,'respectively, by which they can be secured the one, G, to a separator and the other, 7, to an exhaust-pipe. The pipes shown are arranged one above the other and at an angle to one another, being nearest together at the valve-case l. They are made of metals having different coefcients of eX- pansion, the one, 3, having the greater coefficient and made, say, of solid drawn brass tubing, being arranged at the bottom, and the other, 4, having the smaller coefficient, made, say, of steel tubing, being arranged at the top.

8 is the controlling-valve, consisting of a spindle that extends downward into the valvecase 1 through a stuiiing-box 9. This valve abuts against a lever 10, that is pivoted to an extension 5fL of the bracket or carrier 5, and is prevented from moving in the direction of the arrow a to depress the valve by adjustable nuts 11 on a stud 12, which extends through one arm of the lever 10 and is pivoted to the bracket 5. Between this arm and the bracket 5 is or may be a spring 13, that will v permit the lever to move in the opposite directionviz., in the direction of the arm b'- and allow the controlling-valve 8 to rise and so prevent any undue straining of the parts and damage of the valve-seat by excessive expansion of the tubes. By depressing the long arm of the lever 10 in the direction of the arrow b against the action of the spring 13 the controlling-valve 8 will be permitted to be automatically raised by the luid-pressure on its lower end for the purpose of blowing through the trap when desired.

14 is the main valve, made in the form of .a hollow plunger, through the bottom of which is a central hole 14n, controlled bythe controlling-valve S. This main valve is made a loose fit in the valve-case 1, so that water and steam can flow slowly between it and the valve-case and enter its interior, and is shaped at its lower side to t against a correspondinglyformed seat 1d on the adjacent projecting end of the passage 1l.

The working of the steam-trap is as follows: The tubes 3 and 4before steam is supplied to the pipes to which the trap is connected occupy the position shown approximately in the drawings, the valve-case being in its lowermost position, with the main valve 14 resting on its seat ld and away from the controllingvalve 8, so that it is free to lift. v Upon steam being supplied to the pipes connected to the IOO IOv

separator and trap any water they may contain or which is formed by condensation upon iiowing into the lower pipe 3 of the trap will by acting against the lower side of the main valve lift this valve, and thus open a large outlet-passage through the pipe 4, by which the water can be quickly discharged. The controlling valve 8, which passes tightly through the stuiiing-box 9, will also be forced outward by fluid-pressure upon its inner end until it abuts against the lever 10. Upon steam entering the pipe 3 behind the water it will cause this pipe to expand in length, while the pipe 4 will not expand to the same extent, the result being that the connected movable ends of the pipes 3 and 4, with the valve-case 1, will be raised sufficiently to cause the main valve 14 to be seated against the controlling-valve S and also by the action of the fluid-pressure on its upper side against the seat ld, thereby preventing the escape of steam from the trap. Steam or water of condensation by flowing past the exterior of the main valve 14 and acting upon the upper sidethere of will keep this valve against its seat 1d until by the contraction of the pipe 3, due to water accumulating therein, the valve-case is moved downward and the main Valve 14 consequently moved away from the controlling-valve S, which will be held against the lever 10 by the pressure of the steam or water on its inner end. The controlling-valve will consequently open the hole 14 through the larger or main valve 14 and permit the water that will have collected above this valve to escape through the said hole, and by relieving its upper side of pressure will permit this valve to be raised by the water-pressure on that annular part of its lower surface that is around the seat 1. The main valve being thus opened, water will again be quickly discharged from the pipe 3 through the large passage 1b and pipe 4 until by steam again entering the pipe 3 this pipe expands and again raises the valve-case 1 sufficiently to seat the main valve 14 against the controlling-valve S and close the opening 14, whereupon the duid-pressure will again force the main valve against the seat 1d, and so close the opening 1b. The above-described operation will be repeated intermittently while the trap is in use.

Fig. 2 shows a modified arrangement in which the outer end of the controlling-valve 8 is kept in contact with the lever 10 by a coiled spring 15, that encircles it and is 1ocated between a head 8a on the valve and the gland of the stuiiing-box 9.

1. In an expansion steam-trap, the combination with a water-discharge pipe adapted to expand and contract by contact alternately with steam and water of condensation, of a compound-valve arrangement comprising a valve-chamber arranged to be moved alternately in opposite directions by expansion and contraction of said pipe and having a relief-opening, a main valve arranged to work in said valve-chamber and adapted to open and close the outlet of said pipe by variation in fluid-pressure on its two sides, and a supplementary valve adapted to control said relief-opening, substantially as described for the purpose specified.

2. In a steam-trap, the combination of a water-discharge pipe provided with a valvecham ber having a relief-opening,a m ain valve mounted to work in said chamber and adapted to open and close the passage through said pipe by variation of fluid-pressure upon its opposite sides, a normally lixed supplementary valve adapted to control said reliefopening, and an expansion device arranged to be subjected alternately to the heating action of water and steam and, by consequent contraction and expansion, to alternately move said valve-chamber and main valve away from and toward said controlling-valve, whereby said relief-opening will be alternately opened and closed, the Huid-pressurer on one side of the main valve decreased and increased relatively to that on the other side,

and said main valve permit-ted to open and close.

3. In a steam-trap, the combination of two connected water-discharge pipes having dif:- ferent coeflicients of expansion, a valve-case carried by said pipes, a main or large valve arranged to work loosely in said valve-case and control an opening between said pipes, and a smaller valve adapted to control a relief-passage through the larger valve and operating to open and close said passage by movement of the one valve relatively to 'the other due to unequal contraction and expansion of said pipes when subjected alternately to the action of water and steam admitted thereto.

4. In a steam-trap, the combination with the water-discharge pipe of the trap, of a stationary controlling -valve, a valvechamber provided with a relief-openin g and carried by a part of the trap subject to changes in temperature and consequent expansion and contraction whereby said valve-chamber will be moved alternately toward and from said controlling-valve and cause the same to alternately close and open said relief-opening, a main valve arranged to work in said valvechainber and control the escape of water through said pipe, and a passage whereby water can enter said valve-chamber and act differentially upon the two sides of said main valve, substantially as herein described.

5. In a steam-trap, the combination with two water-discharge pipes .fixed at one end and movable at the other, of a valve-case connecting the movable ends of said pipe together and formed with passages whereby the one pipe can be placed in communication with the other, a main valve mounted to work in said valve-case and formed with a reliefopening therethrough, said valve'being adapted to close one of the passages through said slave-i 3.

valve-case and to be then subjected over part of one of its sides to the pressure of waterin the other passage, another passage through which water can pass to the opposite side of said main valve, and a normally stationary controlling-valve adapted to open and close the relief-opening through said main valve when said valve is moved from and toward said controlling-valve by one of said pipes contracting and expanding to a greater extent than the other,substantiall y as described.

6. An expansion steam-trap comprising two pipes inclined to each other and one of which serves for the collection of water of condensation and is adapted to be connected to a water-separator or steam-pipe, the other of which serves as a discharge-pipe,and both of which are fixed at one end, a valve-case connected to the free ends of said pipes and formed with two passages one of which is in direct and free communication with the water-discharge pipe and has an upward tubular extension forming a valve-seat and the other of which is in direct and free communication with the water-collecting pipe and surrounds the tubular extension of the other passage, a main valve mounted to work in said valve- Case, formed with a relief opening therethrough and adapted at one side to be seated against said tubular extension and to be subjected over part of such side to pressure of water in the water-collecting pipe, a passage whereby Water can flow from the water-collecting pipe to the opposite side. of said main valve, and a normally stationary controllingvalve extending into said Valve case and adapted to open and close the relief-opening through said main valve when said yvalve-case is moved from and toward said controllingvalve by contraction and expansion of said water-'collecting pipe, substantially as described.

7. An expansion steam-trap comprising a carrier, two metal pipes 3 and 4 inclined to each other, fixed at one end to said carrier and adapted to be connected the one to a water-separator or steam-pipe and the other to a -drain-pipe, a valve-case connecting the opposite movable ends of said pipes and formed with a stuffing-box and with passages l, l" that are in free communication respectively with the pipes 3 and 4, the passage ilb having a tubular extension adapted to form a seat ld and surrounded by the upper portion l of the other passage la, a hollow main valve loosely fitting said valve-case, formed with a relief-opening located above said passage ll and adapted at its lower side to seat itself upon and overlap the seat 1, and a normally stationary controlling-valve extending through said stuffing-box and controlling the relief-opening in said main valve, substantially as described.

8. An expansion steam-trap comprising a carrier, water-discharge pipes 3 and .4 inclined to each other and fixed at one end to said carrier, a valve-case connecting the opposite ends of said pipes and having passages therethrough adapted to place said pipes in communication with each other, a main valve mounted to slide in said valve-case, formed with a relief-opening and adapted to close the communication between said pipes and leave a portion of its lower side subject to the pressure of water in the pipe 3, a passage whereby water can pass to the upper side of said valve, a controllingvalve extending through said valve-case and arranged to control said relief-opening, means for normally limiting the movement of said controllingvalve in a direction to open said relief-opening, and a spring for enabling said controlling-valve to yield when subjected to undue pressure, substantially as herein described for the purposes specified.

Signed at 2 Popes Head alley, Cornhill, London, E. C., this 19th day of April, 1898. JOHN ISAAC THORNYCROFT. JOHN EDWARD THORNYCROFI, Witnesses:

EDMUND S. SNEWIN, WILLIAM CRoss. 

